Control/conditions
HEAT
When defrost operation
begins, frost has formed
on the outdoor unit
(when the ambient air
temperature is low).
Defrost operation begins based on outdoor
heat exchanger temperature and outdoor
air temperature conditions.
Non-stop defrost
(Refer to Fig. 1)
1. After HEAT operation begins, the temperature
of the outdoor heat exchanger is at or below the
L1 line for 35 minutes.
(If outdoor air temperature is less than 26.6
°
F,
the time is 48 minutes)
2. After HEAT operation begins, the temperature
of the outdoor heat exchanger is at or below the
L2 line for 120 minutes.
The 4-way valve remains ON during defrost.
Non-stop defrost
Unit operation
Explanation
The outdoor fan stops and the solenoid
valve turns ON, allowing the refrigerant to
bypass the indoor unit.
Indoor fan : Stopped
Outdoor fan : Stopped
Compressor : 80 Hz
Solenoid valve (for hot gas bypass): ON
4-way valve : Remains ON
Operation lamp : Red and orange ON
alternately
Defrost release
Indoor fan turns ON.
After 10 seconds, the solenoid valve
(for hot gas bypass) turns OFF.
When the cold air feel has disappeared,
the indoor fan starts and gradually increases
speed until it reaches the set speed.
STOP
[Clean defrost]
Defrost is performed
when the outdoor unit is
stopped, and the
temperature of the
outdoor unit coil is at or
below the L1 line.
(Refer to Fig. 1.)
All indicator lamps turn OFF. The indoor and
outdoor units stop.
The operating frequency during defrost is
80 Hz. (Frequency is lowered if the current
peak cut-off function is activated.)
The maximum length of a single defrost
operation is 12 minutes.
For the outdoor heat exchanger temperature
conditions for ending defrost, refer to Table 1.
Operation is restarted
within 4 hours (only when
AUTO mode is selected
with the remote
controller).
Within 4 hours after operation was stopped, it is
assumed that there has been no significant
change in the indoor and outdoor temperatures,
and the previous conditions (HEAT) are stored.
Starts operating in the same operating mode
(HEAT) and with the same temperature
settings as before operation was stopped.
Operation starts after 4
hours or more have
passed.
New operation begins based on the
temperature conditions at the time the
ON/OFF button is pressed.
The thermostat turns ON.
The unit operated before, and the temperature of
the indoor heat exchanger is relatively warm.
Therefore,the fan speed may start at the set fan
speed at the same time that the thermostat turns
ON.
The indoor unit is stopped.
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